GB/T 17241.1-2024 Cast iron pipe flanges - Part 1: PN designated
1 Scope
This document specifies the styles and parameters, types and dimensions, technical requirements, pressure test, inspection and acceptance, marking and labeling, and ordering requirements and packaging of PN designated cast iron pipe flanges and blank flanges.
This document is applicable to cast iron pipe flanges and blank flanges made of gray cast iron, ductile cast iron and malleable cast iron, nominal pressures PN 2.5 ~ PN 63 and nominal dimensions DN 10 ~ DN 4000.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 152.4 Fasteners - Counterbores for hexagonbolts and nuts
GB/T 1047 Pipework components—Definition and selection of nominal size
GB/T 1048 Pipework components - Definition and selection of nominal pressure
GB/T 7306.1 Pipe threads with 55 degree thread angle where pressure-tight joints are made on the threads - Part 1: Parallel internal and taper external threads
GB/T 7306.2 Pipe threads with 55 degree thread angle where pressure-tight joints are made on the threads - Part 2: Taper internal and external threads
GB/T 9439 Gray cast irons
GB/T 9440 Malleable iron castings
GB/T 12716 Pipe threads with the thread angle of 60 degrees where pressure-tight joints are made on threads
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 1047 and GB/T 1048 apply.
4 Types and parameters
4.1 Nominal pressure
This document specifies the following 7 pressure classes identified by PN for nominal pressure:
The types of flange sealing faces are divided into flat face and raised face, in which the flat face code is FF and the raised face code is RF, as shown in Figure 1. The sealing face type of ductile iron flange and gray cast iron flange should be raised face: the sealing surface of malleable cast iron flange can flat face and raised face.
The transition from the outer diameter of the sealing surface of the flange to the connecting face of the flange can be chamfered or rounded, and is determined by the manufacturer.
Contents Foreword i Introduction ii 1 Scope 2 Normative references 3 Terms and definitions 4 Types and parameters 4.1 Nominal pressure 4.2 Nominal dimensions 4.3 Types and codes of flange sealing faces 4.4 Flange types, codes and their application scope 5 Types and dimensions 5.1 Integral cast iron pipe flanges 5.2 Hubbed screwed cast iron pipe flange 5.3 Cast iron pipe flanges with hubbed slip-on-welding and hubbed socket welding 5.4 Cast iron pipe blank flanges 5.5 Cast iron pipe flange with weld-on collar 6 Technical requirements 6.1 Flange material 6.2 Pressure-temperature rating 6.3 Dimensional tolerances 6.4 Roughness of flange sealing face 6.5 Machining and manufacturing 6.6 Fasteners and sealing gaskets 6.7 Repair 7 Pressure test 8 Inspection and acceptance 8.1 Inspection 8.2 Acceptance 9 Marking and labeling 9.1 Marking 9.2 Labeling 10 Ordering requirements and packaging
